DE 196 00 852 A1 has disclosed a cup tappet for an internal combustion engine, which cup tappet is connected between a control cam and a valve. The cup tappet has a skirt which is configured to be approximately hollow-cylindrical and is guided in a hole of the cylinder head. The skirt has a radial recess, into which an anti-rotation element is inserted which prevents rotation of the cup tappet around the lifting axis relative to the cylinder head by the anti-rotation element engaging in the circumferential direction both into the cup tappet with a form-fitting connection and into a suitable groove of the cylinder head. For this purpose, the anti-rotation element protrudes out of the skirt in the radial direction. According to a first embodiment, the anti-rotation element is configured as a cylinder body, the longitudinal axis of which is oriented in the lifting direction and the end faces of which have grooves which open radially from the outside and into which a projection of the skirt engages. That circumferential surface of the anti-rotation element which lies outside the skirt engages into the groove of the cylinder head, while the inner circumferential surface bears against an inner body of the cup tappet. In accordance with a second embodiment, the anti-rotation element is configured as an elastic spring element in the form of a U-shaped clasp with two limbs and a back. The limbs of the clasp are inserted radially inwards into the recess of the cup tappet under elastic deformation, until embossed portions of the limbs latch into the limits of the recess of the skirt in the circumferential direction. According to a third embodiment, the anti-rotation element is configured as a slotted sleeve in the shape of a hollow cylinder, the longitudinal axis of which is oriented in the lifting direction. The sleeve has embossed portions which lie opposite one another and into which the limits of the recess of the skirt latch in the circumferential direction under elastic deformation of the sleeve.
DE 28 29 423 C2 has disclosed an anti-rotation element which does not serve to guard against rotation between the cup tappet and the cylinder head, but rather between individual components of the cup tappet. The special feature of the anti-rotation safeguard which is known from this publication is that, in addition to the function as an anti-rotation safeguard, it serves to supply oil through a central oil supply hole.
DE 41 15 670 A1 has disclosed an anti-rotation element which is configured as a shaped part and as a thin-walled sheet-metal or plastic part. The shaped part is supported centrally on a web of the cylinder head and, away from the said web, bears against two cup tappets in order to safeguard the latter against rotation. Here, the shaped part is fixed definitively by the camshaft being mounted or the shaped part being clamped between a guide housing and the cylinder head.
DE 43 24 756 C2 discloses a cup tappet which has an outer cup with an inner tappet which is guided in the outer cup such that it can be moved in translation by way of a hydraulic compensating element. An anti-rotation element engages such that it can move in translation into a guide groove on the receptacle hole in the cylinder head and into an aperture of the outer cup. In addition, the anti-rotation element engages into a guide groove of the inner tappet with a relatively large inner guide length or contact face. This increased inner guide length serves for reliable guiding between the inner tappet and the cup and prevents tilting of the outer guide length in the guide groove of the cylinder head. As a result, the production of chatter marks is avoided in the guide groove, which chatter marks could lead to jamming.
DE 195 01 061 A1 has disclosed a cup tappet, in which an inner part is in contact in a skirt. In this case, the anti-rotation element does not protrude beyond the inner casing of the skirt. The inner end face of the anti-rotation element is configured in accordance with a part segment of a circumferential surface of a cylinder, with the result that a large surface area of the inner part can bear against the abovementioned end face and an inner casing surface of the skirt.
DE 199 57 772 A1, for example, has disclosed an anti-rotation element which is of cylindrical configuration with its longitudinal axis in the direction of the lifting direction. The casing surface which is arranged so as to lie outside the cup tappet is guided in a guide groove with a circular segment-shaped contour in accordance with the outer contour of the cylinder.
Further anti-rotation elements are known, for example, from DE 101 23 966 A1 and DE 43 37 330 A1.